Baking oil



Patented July 15, 1941 Frank W. Corker-y, Grafton, Pa... ass'ignor to Falk,

a Company, a corporation 01' Pennsylvania No Drawing. Original application July 1c, 1938.

Divided and this applica tion March 2-1, 1941, Serial No. 385,547

. (Claims. (Cuzco-23) Serial No. 219,613.

This invention relates to the production of oils of the type adapted to inclusion in abaked coat ing. The application herein iorms a division of my co-pending application Serial No. 219,613,

' filed July 16,1938.

The object or the invention is to produce an oil or oleo-resinous composition (which latter will be herein considered as falling generically within'the class of oils) having the size of a preponderant proportion 01- its molecules so increased that, by virtue of such structure, the oil has minimized qualities of penetration. This I eflect while retaining the solubility of the oil in organic solvents, with consequent capability of the oil when diluted, or out back, to flow freely,

to have'good spreading qu'alities, and adequately to level 011 when applied as a coating.

, Although the process of kettling saponifiable oils, or the sort known as drying oils and semidrying oils, involving polymerization, molecular rearrangement, and intra-molecular changes, increases the molecule size of the oils, the effect thus obtainable is rather rigidly limited by the relative proportion of the glycerides or unsaturated and saturated fatty acids inthe oil. Polymerization is attended by a decrease in drying qualities. Blowing the oil with air, while heating to a temperature below the stage at which polymerization takes place, tends to increase the average molecule size 01' the oxidizable constitucuts of the oil. In itself, however, polymerization does not result in the building of molecules of extremely great size, to produce an oil notably lacking in ability to penetrate, nor does it greatly improve the drying and film-forming characteristics of the oil. It a blowing operation be conducted under temperature conditions of a severity suiiicient to cause polymerization. it has a very detrimental effect on the color of the oil and certain other qualities of the oil. Sequentialiy to kettle the oil, and to blow it in accordable oil, and gelation being thus held 011, blowing oi the oil is continued additionally to effect oxidation therein.

ance with standardpractice gives but little efiect from the blowing operation.

.In my co-pending application Serial No. 195,- 345, filed March 11, 1938, and Serial No. 209,533, filed May 25, 1938. I have disclosed processes in which an oxidizable oil, such as a drying oil, or semi-drying oil, is carried to a high stage of oxidation by blowing. In the methods disclosed in those applications, the oil is blown, under conditions avoiding substantial polymerization therein, up to a stage at which gelation or the oil is imminent. At such stage the gel structure which has been formed in the oil is dispersed by the addition or an oil solub'le resin, or a raw oxidiz- It is further my discovery that this procedure may be practiced sequentially after kettling, to

oxidize to a maximum extent the oilwhich has been polymerized by the kettling, and thus to obtain an oil a large proportion of the molecules of which have been increased to. a size not previously obtained without physical gelation or the oil. As a matter of greater importance, the drying qualities, which have been impaired by polymerization, are in large measure restored. The product of this process, involving the step 01 kettllng as an initial procedure, and a procedure in accordance with the principles of my oxidation process, modified to suit the condition of the oil acted upon in the blowing treatment, is an oil notably lacking in qualities oi penetration. It has fair drying qualities, and is peculiarly adapted to use in baked coatings. Its adaptability to this purpose is of novel sort, in that it not only tends to remain upon porous surfaces without penetration, but also is capable of overlying a coating of thermo-plastic nature, without penetration by the two coatings under temperatures to which they are subjected in heat drying.

In order to illustrate the principles of my invention, and to give specific guide for its useful' employment, I shall now exemplify it as follows:

Example No. 1

A batch of 1000 pounds of fish oil was heated ior about 1.5 hours to a temperature within the range of 500 F. to 600 F. This resulted in a reduction of its iodine value from about 180 to about 100. Its viscosity was thus increased from about Saybolt seconds at 210- F. to about 250 Saybolt seconds at 210 F., and from about body A. on the Gardner-Holt scale to about body T; The oil by its kettling had been deprived of about W1 01 its initial capacity for oxidation.

The kettled oil was introduced into a blowing vessel equipped with heating coils and with per-.

iorate coils for the introduction or air. The

batch was maintained at a temperature of about 250 F., and by means 01' an adequate blower, air was blown through it at about the standard rate of blowing or 1.65 cubic feet of air per pound of the batch per hour. At the end of about seven hours the viscosity oi the batch had increased to about 1100 Saybolt seconds at.210 F.; at the end of about 8.5 hours it had increased to about 1450 Saybolt seconds at 210 F.;- aiter about 10 hours to a similarly determined -viscosity oi about 1840;

and after 11 hours to a similarly determined viscosity or about 2300. Blowing was continued for a total initial period oi! about 12 hours, at the end of which period the viscosity of the oil had been increased to about 3000 Saybolt seconds at 210 F.

, At this stagegelation being imminent, there was added 1000 pounds 01' ester gum, having a melting point of about 190 R, the addition of the ester gum serving to disperse the gel structure formed by the initial blowing treatment, Blowing was then continued for a further period of about four hours, at which stage the oil was considered t'ohave received its maximum treatment from the procedure. I,

The resultant oleo-resinous product had a melting point of about 96 F. and was soluble in both the aromatic hydrocarbon solvents and the aliphatic hydrocarbon solvents. It flowed readily and levelled oi! well when diluted in equal weight with either of those solvents and dried in' about 15 hours in air. It has proved to be an stage 01 the-blowing, 600 pounds of rosin was added, and blowing was continued for a further and additional period of about three hours, at

which stage the product (when cooled) was a semi-solid, having a viscosity of about 2700 Saybolt seconds at 210' F.

The product was soluble in both the aromatic hydrocarbon solvents and the aliphatic hydrocarbon solvents. When out with an equal weight of solvent, the solution has a body or A to B on the Gardner-Holt scale. The oil dries in air in about excellent'oil for use in, or as, a baked coating. v

. 'Ezample No. 2 I

A batch 01' 3000 pounds of soya bean oil was kettled for about hours at a temperature within the range of 500 F. to 600 F. By this kettling the viscosity oi the oil was increased from about 100 Saybolt seconds at 210 F. to about 200 Saybolt seconds at 210 F., and from about a body A on-the Gardner-Holt scale to about a body Q on that scale. The initial iodine value of the oil was about 135 and this was decreased by kettling to about 93. a

The kettled oil was introduced'into a blowing vessel and was blown as in Example No. 1 for a total initial period of about 17 hours. At the end of that initial blowing period physical gelation of the oil being imminent, there was added an equal weight of ester gum to disperse the gel structure formed during the initial blowing, and

' blowing was continued for an additional period of about five hours. when gelation again became imminent, the treatment was considered to have been finished.

The resultant oleo-resinous product was closely analogous to that obtained in Example No. 1. It had a melting point of about 96 F. and was soluble in both the aromatic hydrocarbon solvents and the aliphatic hydrocarbon solvents. When diluted with an equal weight of either of those solvents, a film of the oil dries in about 20 hours. It has proved'to be an excellent oil for use in or as baked coating. 1

The foregoing is exemplary-'01 my method in application of its principles to the treatment 01' semi-drying oils. As exemplary of my method in practice of its principles upon one of the standard drying oils (linseed oil and perilla oil) give the following example:

Example No. 3

A batch of 1400 pounds 01' perilla oil was raised to a temperature of about 550 F., and was held at that temperature for about1.75 hours. The viscosity of the oil was increased by this kettling from about 100 Saybolt seconds at 210 .F. to about 500 Saybolt seconds at 210' I".

The 011 thus treated was introduced into a blowing vessel, and was blown under the same conditions described in the preceding examples, save that the temperature of the batch was maintained at about220 F. After blowing for about 9 hours, a viscosi y of about 3000 Saybolt seconds had been attained, and the batch had reached a point atwhich gelation was imminent. At that 75 All viscosities which are. given were taken on the Saybolt furol viscosimeter. Where drying time is given, it is to be understood that this drying time is based upon tests made in accordance with an accepted procedure for the estimation of rates of drying. This test consists in bringing the blown oil back to the viscosity of a corresponding raw oil by the addition oi. a suitable solvent; adding' selected oil-soluble lead, cobalt or manganese driers in thequantity commonly thus employed,

and spreading the material in a thin film so that after drying the film is between 0.002 and 0.004

of an inch, which drying is eifected at 77 F. and

about 50 relative humidity. Although the cilia polymerized before blowing, the blowing operation is in each instance conducted at such temperature that in it no substantial further polymerization is caused.

It should be explained that, if desired, a mixed oil, such, for example, as a mixture of soya bean oil and perilla oil, or a mixture of soya bean oil and fish oil, may be subjected to treatment. Instead of ester gum any of the oil-soluble thermoplastic resins may be used to replace the ester sum for addition at the end of the initial blowing period. to eflect dispersion of the gel structure in the batch. Coumarone resins, petroleum resins, and rosin are typical of the oil-soluble thermoplastic resins which may be used for the purpose. In effecting gel dispersion by means of various resins, it is desirable to vary the relative proportions of the oil contained in the initial batch and the resin inversely to the oil-solubility or the resin used. Mixtures of two or more resins may successfully be used. I have found that gel dispersion may be eflected by adding resin within the range of 20 and 70%, the weight of the final batch resulting from its addition.

The product of my method in any 01 its var-- iants exemplified or suggested above has quail ties rendering it peculiarly adapted for-baked coatings. When applied to highly porous substances, the great increase in the molecule size of a large irom'the oxidation wholly prevents penetration of the oil into the porous body upon which it is laid. On' the other hand it has good solubility in the solvents commonly employed, givingit good spreading qualities, and permitting it to level oi! well when applied. A baked film of the oil is both hard and elastic, and has good adhesion.

Probably the most remarkable quality of the oil obtained by practicing my method is that although it has been initially deprived'o! a great proportion of its drying capacity by polymerization, the final blown product has drying qualities closely comparable to those of the initial raw oil.

This is attributableto the 'twostage blowing process to which the oil is subjected, with gel disproportion 01 its constituents resultant sequential steps of polymerization and molecular structure.

resin, at an intermediate stage as closexas possible to the point at which continued blowing would result in bodily gelation of the batch. The followingtheory is advanced to explain the remarkable result of restoring drying qualities of a kettle'd oil with depriving the oil of the effects of polymerization obtained by kettling. Initially the mechanics involved may be illustrated by comparing the composition of a raw soya bean oil, a raw linseed oil and a soya bean oil subjected to my novel two-stage blowing operation.

Raw linseed oil contains the glycerides of oleic acids, linoleic acids, and linolenic acids in such proportion that the glycerides of the unsaturated fatty acids represent approximately 72% of the oil, while inactive fatty acid glycerides (preponderantly olein) are approximately 28% of it. Whileit is not technically correct to say that olein is a saturated glyceride, it is a normally unreactive glyceride, with only one double bond and no conjugated double bonds, .in its Although these. glycerides include relatively small proportions of ste'arin, palmitin, and palmitolein, olein so preponderates that the sum of these glycerides will hereinafter be referred .to generically as oleln." When spread in a film, the oil dries by absorbing oxygen from the air, and gels are formed, of the glycerides of the linoleic and linolenic acids, while the film is renderd continuous by the dispersing eiIect of the olein. Linseed oil is so balanced in its unsaturated and saturated constituentsthat in its raw condition the oil dries normally to agood coating.

Soya bean oil differs from linseed oil in that its content of olein is much greater than the olein content of linseed oil; thus when'a film of raw soya bean oil is spread, and oxidation takes place, the dispersing eifect of the olein on the gels formed by the oxidation of the unsaturated glycerides is so great that a very soft film is produced. When either linseed oil or soya bean oil is kettled, polymerization decreases the ability .of its content ofunsaturates to absorb oxygen,

so that the drying time is lengthened. Polymerizationin the oil has very little effect on the type of film produced, save that the increase in viscosity increases the fiow (i. e. the levelling qualities) of the oil. When either linseed or soya bean oil is blown, the unsaturates are given an initial oxygen addition, the linkage being relatively weak, so that the blown oils, when spread in a film, dry slightly faster than corresponding raw oil, but theinherent film characteristics of the oilare not greatly aflfected. I

In the new treatments outlined above, the dispersing effect of the non-volatile, solvent olein is partially inhibited in the following manner:

When soya bean oil is preoxidized to a' high stage of preoxidation, there is consequent increase in the size of the oxidized moles to a point at which-gelation normally wouldtake place if oxidation were continued. By adding oil-soluble thermoplastic resin, these large moles are then dispersed in normal moles, andblowing is continued. In this step of the process,blowing'is continued to a stage in which the portion of the term "oxidizable drying oil as used in the ap-.

oxidized condition being in decreased measure dispersed in the olein present. The large size of some of the moles requires a larger than normal amount of olein moles to' coat them, and to render a film of the oil continuous.

Thus, it can be seen that by the treatment of my method I have in effect destroyed the property of the semi-drying soya bean oil (taken as exemplary) to dry to a tacky film. Thisis because the plasticizing action of the olein is expended in spreading over and coating moles of unusually great size, thereby decreasing the dispersive effect of the olein by' rendering more exacting the performance of its primary function in imparting continuity to a film'of the oil. The olein thus does not in normal measure inhibit further oxidation of the partially oxidized moles in a film of the oil, either to retard drying oxidation or to prevent its continuance to the stage of hard film formation.

capacity for oxidation and consequently of their drying qualities, the residual capacity for oxida-.

tion in those constituents of the oil has been utilized to produce the phenomena above described.

This results in restoring wholly or in large measure the capacity of the oil to air-dry ina fihn. The oil, though having in increased measure thenon-penetrating qualities of a kettled oil, may nevertheless be used to form an airdried film in a manner in which an oil kettled by standard practice nray not. Further, the quality of the oil as a non-penetrating baked coating. is enhanced. A very important use of my product is in the manufacture of oilcloth, in which a layer of the coating is laid over a'layer of asphalt, pitch, or wax. In baking, there is no inter-penetration of these two layers of different substance, but on the contrary the oil dries to a hard coherent film, adherent to, butthe goodfilm-forming qualities of my oil, gives an oil almost perfect for such purposes. I

China-wood oil, because of the intermolecular and intramolecular effects peculiar to it, cannot by itself be subjected to my process, and cannot be included in substantial proportion to make with standard drying oils and semi-drying oils a blended starting material. While, therefore, the

pended claims is to be taken as defining generically the standard drying oils- (linseed oil and perilla oil) and thesemi-drying oils (fish oil, sardine oil, pilchard oil, scya'bean oil, sunflower seed oil, rape seed oil, saiiiower oil, walnut oil, etc.)-, and various blends ofthese oils, it is to be understood as excluding China-wood oil, and

oil initially blown is converted to approximately its maximum gel structure, while the'gels are held in dispersion by the partially oxidized other constituents of the oil, and .by the resin. The treated oil then contains moles of oxidized linoleic and linolenic glycerides which have absorbed their full content of oxygen, and also contains blends containing a substantial proportion of that oil. 1

I claim as my invention: 1. The herein described method of treating oxidizable drying oils to produce a baking oil of particularly high non-penetrating qualities which comprises effecting polymerization in an oil having drying qualities and having a capacity for polymerization less than that of China-wood oil moles on which only partially oxidation has been f effected. the unsaturates in various degrees of r by heating the said drying oil to a polymerizing temperature within the approximate range of 500* F. to 600 F. to a stage in which the oxidizable constituents of the oil are in large measure deprived oidrying qualities but retain residual capacity for oxidation; and restoring to the said oil drying qualities lost by p erization by blowing air therethrough at an oxidizing tempering gel dispersion in the batch by introducing oil-soluble thermoplastic resin as an oil-soluble film-forming gel dispersant, and after such gel dispersion continuing to blow air through the batch for a substantial blowing period to a stage at which the viscosity of the oil hasbeen further increased without gelation oi the oil. A

2. The herein described method of treating oxidizable drying oils to produce a baking oil of particularly high non-penetrating qualities which comprises effecting polymerization in an oil having drying qualities and having a capacity for polymerization less than that of China-wood oil by heating the said drying oil at a polymerizing temperature within the approximate range of 500 1''. to 600 F. to a stage in which the oxidiz able constituents of the oil are in large measure deprived oi drying qualities lost by polymerization by blowing air therethrough at an oxidizing temperature to a stage of preoxidation at which gelation o! the oil becomes imminent, at such stage eflecting gel dispersion in the batch by introducing an oil-soluble thermoplastic resin as an oil-soluble thermoplastic gel-dispersant in a quantity equal to about 20% to 70% the weight of the total batch resulting i'rom its addition, and after such gel dispersion continuing to blow air through the batch for a substantial blowing period to a stage at which the viscosity of the oil has been further increased without gelation oi the oil.

3. The herein described method oi treating oxidizable drying oils to produce a baking oil or particularly high non-penetrating qualities which comprises effecting polymerization in an oil hav-.

ing drying qualities and having a capacity for 2,249,116 I r i a polymerization less than thatoi China-wocdoil jby heating the said drying oil to a polymerizing temperature within the approximate range of 500 1''. to 600 F, to a stage in which the oxidiz- V able constituents of the oil are in large measure deprived of drying qualities but retain residual capacity for oxidation; and restoring to the said,

oil drying qualities lost by polymerization by-blow ing-air therethrough at an oxidizing temperature to a stage 0! preoxidation at which gelation 061 the oil becomes imminent, at such stage efiecting gel dispersion in the batch by introducing oilsoluble thermoplastic coumarone-indene 165m as an oil-soluble film-forming gel dispersant, and

after such gel dispersion continuing to blow air through the batch for a substantial blowing period to a stage at which the viscosity of the oil has been iurther increased without gelation oi the oil.

4. The herein described method of treating.

comprises eflecting polymerization in an oil having drying qualities and having a capacity for polymerization less than that of China-wood oil by heating the said drying oil at a polymerizing temperature within the approximate range 01' 500' 1". to 600 F. to a stage in which the oxidiza'ble constituents of the oil are in large measure deprived of drying qualities; and restoring to the said 011 drying qualities lost by polymerization by blowing air therethrough at an oxidizing temperature to a stage of preoxidation at which gelation or the oil becomes imminent, at such stage effecting gel dispersion-in the batch by introducing oil-soluble thermoplastic coumarone-indene resin as'an'oil-soluble thermoplastic gel-dispensant in a quantity equal to about 20% to 70% the blowin period to astage at which the viscosity or the oil -has been further increased without gelation or the oil. 

